The ruling struck down parts of McCain-Feingold, wasn't M-F the will of the people?
As far as your second question, I read the papers and follow politics pretty closely-- not on the expert level, but close, and don't remember anything about this case either in the papers or on various forums until it was a done deal. Maybe it's because the case started during the 2008 campaign season and got lost in the background of all the other issues around Hillary and Obama, I don't know, but wonder how many people were aware of it over the years. Apparently it wasn't a hot-button topic that gets closely followed, like 2nd amendment cases, for example.
But to wind this up, how does the time line of polling apply? One February poll showed 80% opposition to the ruling, and this included 76% who called themselves conservative Republicans.